In order for you to play Guns of Icarus Online on Linux with minimal graphics settings, your computer must meet the following requirements
Operating System:
Ubuntu 12.04 LTS, 32-bit (Linux machine configuration not supported)
Processor (CPU):
Dual-core 2 GHz
Memory (RAM):
2 GB RAM
Graphics Card:
Intel HD3000, Nvidia GeForce GT8600 or equivalent, supporting Shader Model 3 equivalent
Hard Drive:
3 GB HD space
Other Requirements:
Broadband Internet connection